The present invention relates generally to communication networks, and more specifically, to a hierarchical QoS behavioral model that includes as a component a hierarchical packet scheduling behavioral model.
High speed networks are designed to carry services with a wide range of traffic characteristics and quality-of-service (QoS) requirements. Traffic management mechanisms provide a variety of QoS behaviors (e.g., policing, marking, low latency service, bandwidth allocation services) in routers and switches. A common task for the packet scheduling component of the QoS behavioral model is ensuring that each of multiple queues is guaranteed a minimum rate, excess bandwidth is shared in accordance with predefined weights, each queue does not exceed a specified maximum rate, and the link is maximally utilized within the maximum rate constraints.
Many different QoS behavioral models have been defined, and this can be confusing to users that want, or require, a consistent model across the entire network. In some cases, individual platforms or implementations have a different means to enable basic QoS functionality or have unique internal system bottlenecks (e.g., a switch fabric, an encryption engine) whose resources must be managed directly (via platform specific CLI (Command Line Interface)) in order for the user to achieve basic QoS goals (e.g., provide low latency to voice traffic). In such an environment, users must acquire knowledge and expertise of platform specific architectural issues and essentially learn multiple ways to achieve what is really the same goal (i.e., define the QoS behavior on a product). Users want a common and consistent interface, and the historical lack of such commonality and consistency is a serious problem for many deployments involving multiple platforms. A uniform interface is a key component to successfully providing customers with an end-to-end QoS solution.
There is therefore, a need for a highly functional QoS behavioral model that can be used on various components and platforms.